It seems that brcmfmac does not support changing the MAC address while the interface is active (POWERED_ADDR_CHANGE is missing from its capabilities), thus preventing the default setting of NetworkManager to use random mac addresses.
The only thing I don’t understand is why I run into this now. Either after updating to Fedora Asahi Linux 44, or after resyncing firmware from within MacOs.
Another thing I noticed is that WiFi OWE (Opportunistic Wireless Encryption) seems not to be supported/working.